US1778316A - Header for ingot molds - Google Patents

Description

O 14, 1930- A. FORREST 1,778,316

HEADER FOR INGOT HOLDS Patented Oct. 14, 1930 UNITED STATES PATENT orries ANDREW FORREST, OI CHICAGOfILLINOIB, ASSIGNOB, BY Hm ASSIGNMENTS, REPUBLIC STEEL-CORPORATION, OI YOUNGSTOWN, OHIO, A CORPORATION m JERSEY HEADER FOB INGOT HOLDS Application December 12, 1921, Serial Io. 889,800. Renewed December 80, 1888.

My invention relates to ingot casting and particularly to mold headers or hot-tops whichare formed or provided with refracso that theheader metal supplies or fills the.

tory non-conductin inner walls or linings to conserve the heat 0 the metal therein while solidification of the metal in the mold occurs,

pipe cavity formed in the mold metal by shrinkage or segregation while solidifying.

In headers now in eneral use the re ractory material is rapidly destroyed by the abrasive action of the molten metal flowing through the header into the mold and by the sticking of the metal to the refractory material, particularly in its corners; the metal as it is poured through theheader into the mold cuts and abrades this material and wears it away; the metal also works into this material and into the joints where fire-bricks are used and fills its depressions, interstices and rough surfaces so that, it sticks to the header, and when the metal shrinks in solidifying and the header is stripped from the sink-head the refractory material is disintegrated, pitted or broken at one or more laces. The result has been that such headers asted at times for only a single heat or the casting of one ingot, and atbest required renewal of the lining or, substitution of a new header after very 'few heats; in either case the cost of hot-top maintenance and operation, and hence of ingot .production, is considerably increased. f -The ob ects of my nvent on are to minimize the abrasive and sticking actions of the metal on the header wall, and to reduce its normal wear, and thereby increase the number of heats that a header will'run. With these objects in view my invention consists in general in providing the header wall with a facing'or coating of non-carbonaceous refractory material.

My invention may be embodied in various forms of headers, and practical exemplifications are shown for illustrative pur oses in the accompanying drawings, in whic Fig. 1 is a vertical central sectional view through the top of an ingot mold equipped with a header having a passage of circular cross-section;

Fig. 2 is a top plan view of the header shown in Fig. 1; Fig. 3 is a similar view of a header having a passa of octa onal cross-section; and Fig. 4 is a view like F1 1 with the header shown in Fig.3 seated on t e mold.

In the drawings the reference numeral 1 indicates an ingot mold of suitable size and shape, and 2 a metallic header-casin which when in use rests on the up r end of t e mold and is o en-ended and is 0 any desired crosssectiona contour; in Fi 2 the casing is shown as circular and in ig. 3 as octa onal. The casing 2 is usually tapered upward and may be provided with lifting-ears 3 an with a lmmg-seat 4 at its lower end which may be formed as an integralledge as in Fig. 1 or or pulling it ofi. The parts so far describe may be of any suitable material, form and organization, and maybe 'varied in these respects in accordance with the requirements of any desired equipment, as the resent invention may be exemplified or em tops or headers of structions.

The inner wall of the hot-top is provided difierent types and conwith a facing or coatin 6 of'non-carbona-' ceolis material, compose of a suitable pulverized refractory material, referably of relatively high-refractory qua ity, such for example as fire clay, ganister, fire brick, silica sandor chrome ore, and a suitable binder,

such for example as molasses mixed with water. In commercial practice I have successfully employed a compound of two hun- .9 ied in hotdred and forty. (240) pounds of silica fireclay and two (2) quarts of molasses mixed with suflicient water to form a plastic or slush mixture. I have mixed the above amounts of fire-clay and molasses with fourteen and one-half (143 quarts of water and formed astic mixture which was a mortar-like p easily spread on the wall and proved particularly useful and effective where the surface was abraded, pitted or broken, as it plastered up large holes and deeply worn places and restored the shape and smoothness of the surface. In other cases where the inner wall was not so seriously damaged by the metal, as where it had merely crumb-led or disintegrated under the normal wear and tear incident to employing the header, I have used more water to thin the above mixture to the consistency ofpaint, and the slush or slurry so formed when brushed or painted onto the wall successfully repaired such disintegrated and worn places. The proportions of the constituents may be varied within limits which provide a mixture than can be spread on the inner wall and forms thereon an adhesive coating or facing of non-carbonaceous refractory material; In practice I apply a suitable coating of the mixture to the'inner wall of the header before it is used, and between heats when required; and preferably 1- also brush or wipe the plastic coating with the slurry to dress or finish it off to a smoother surface. The mixture penetrates more or less intothe heat-insulating material 5 and fills all irregularities, interstices and cav1t1e s 1n it and any joints between its sections or bricks, and when dry cements and binds the bricks or sections together and forms a hard protective coating therefor. When the molten metal is run into the mold the facing orcoatmg protects the material 5 from the cutting or abrasive action of the flowing metal; this action occurs primarily and generally wholly in the coating and is correspondingly taken .away from the material 5 and minimized therein. Also, the facing or coating prevents the metal from working into the material 5 or intothe joints of its bricks or sections, and so prevents the metal from sticking to the wall of the header. Any sticking action of the metal occurs between .it and the coating, and if the latter sticks to the metal it comes away free from the material 5 when the header is separated or stripped from the sinkhead or ingot and so enables the header to be stripped without serious injury to the material 5, frequently caused by pitting and fracturing, and it also reduces the normal wear of the material 5 caused by its liability to crumble or disintegrate. When the coatingmaterial sticks to the metal in the stripping operation it can be easily and quickly repaired or renewed by wiping or-painting the slurry mixture onto the wall. My invention increases the numberof heats that the headers will last; they haveaveraged in commercial work for casting more than fifty (50) ingots and have frequently lasted for castin between seventy and eighty ingots before renewal of the Insulating material 5 was'necessary. Thus fewer'heade'rs are required to carry on the casting operation and enable the molds to be utilized continuously and the metal to be poured into them for successive heats before they are cold, the freuency of relining the headers is lessened, and t e time and labor required to reline them is greatly reduced. My invention effects econ- In practice I prefer to embody my invention in headers or hot-tops having substantially circular inner walls or bores decreasing in diameter upwardly and formed of longitudinally extending fire-bricks, such as shown for example in Fig. 2, as this organization aifordsadvantages in applying the protective mixture to form a circular passage and in reducing the tendencyof the metal to stick to the facing orcoating and the resulting wear of the latter.

My coating when dry forms a smooth, hard and highly refractory layer which resists the eroding and spalling action of the hot metal, it binds the lining bricks together and greatly increasesthe resistance or insulation of the lining against heat-radiation whereby the header metals fluidity to feed the ingot pipe is prolonged, and it is not readily disintegrated by the high heat of the ingot metal; and these characteristics and advantages persist for many heats or pourings in commercial ingot casting. And as my coating does not extend below the lining on the supporting ledge it is not liable to come in contact with the mold and be broken in assembling'and disassembling the headers and molds; and its hard, smooth sur face affords easy stripping of the headermetal when cool.

I claim: 1. A hot-top for an ingot mold having a lining of fire-brick, and a non-carbonaceous coating on the inner wall of the lining composed of-fire clay and a binder.

2. A hot-top for an ingot mold havinga lining of fire-brick, and which has its inner wall coated with a non-carbonaceous material formed by a mixture of approximately twohundred and forty pounds of fire-clay, two quarts of molasses and fourteen and onehalf quarts of water. i p

3. A hot-top for ingot molds comprising a metal casing adapted to rest on the upper endof a'mold, a lining of fire-bricks for the casing'forming a tapered passage substantial- 1y circular in cross-section, and a coating of fire-clay on the inner surface of the lining forming a circular wall on the tapered passage.

5 4. A hot-top for an ingot-mold having a lining of fire-brick and an inner non-carbonaceous coating formed by amixture of approximately two hundred and forty pounds of heat-insulating refractory plaster 1o material and a suitable binder.

5. A hot-top for ingot molds comprising a metal casing adapted to rest on the upper end of a mold, a lining of fire-bricks in the casing forming a tapered passage, and an inner plaster coating of non-carbonaceous refractory material binding the bricks together and forming a circular wall on the tapered passage.

6'. A header for ingot molds comprising a tapered casing having an inner ledge, a lining composed of a plurality of elongated refractory sections supported on the ledge and extending longitudinally of the casing and forming a tapered passage, and a coating forming a substantially circular Wall on the lining and consisting of a plaster layer of non-carbonaceous refractory material and I an inner slurry layer of similar material.

In testimony whereof I afiix my signature.

ANDREW FORREST.

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